Initially, it is noted that the term “locomotive consist” means one or more locomotives physically connected together, with one locomotive designated as a lead locomotive and the others as trailing locomotives. A “train” consist means a combination of cars (freight, passenger, bulk) and at least one locomotive consist. Typically, a train is built in a terminal/yard and the locomotive consist is at the head end of the train. Occasionally, trains require additional locomotive consists within the train consist or attached to the last car in the train consist. Additional locomotive consists sometimes are required to improve train handling and/or to improve train performance due to the terrain (mountains, track curvature) in which the train will be travelling. A locomotive consist at a head-end of a train may or may not control locomotive consists within the train.
A locomotive consist is further defined by the order of the locomotives in the locomotive consist, i.e. lead locomotive, first trailing locomotive, second trailing locomotive, and the orientation of the locomotives with respect to short-hood forward versus long-hood forward. Short-hood forward refers to the orientation of the locomotive cab and the direction of travel. Most North American railroads typically require the lead locomotive to be oriented short-hood forward for safety reasons, as forward visibility of the locomotive operating crew is improved.
In a locomotive consist, it is generally important that the order and orientation of the locomotives is known to the operators of the lead locomotive as well as the computers controlling the locomotives. While there can be many reasons for this, at least one is that the order of the locomotives in the locomotive consist must be known so that the correct operating instructions can be sent to the correctly identified trailing locomotives. In the past, there have been automated and non-automated methods for determining the positions of locomotives in locomotive consists. One known method is for the operator to manually identify the locomotive order and manually record each locomotives relative position in the consist. However, this method is prone to potential operator error. Furthermore, it cannot be accomplished as quickly as desired, particularly when large consists are involved or if the weather is poor or dangerous.
There are known automated methods for determining the location of the locomotives in a locomotive consist. For example, US Publication No. 2001/0044695 entitled Methods and Apparatus for Locomotive Tracking describes a method and apparatus wherein a GPS system is used to determine the specific locations of the locomotives in the consist. However, the methods and systems described in the '695 publication can have problems. For example, GPS systems are prone to failure and/or can be disabled by cloud cover, weather, tunnels etc. Furthermore, not all locomotives in a consist may be equipped with the desired GPS equipment. These “ghost” locomotives must be accounted for manually by the operator thereby resulting in potential errors and inconsistencies for the reasons discussed above.
The disclosure herein is directed to overcoming one or more of these issues as set forth above.